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126. These differences in numbers are due to dissimilar criteria used to estimate endangerment, different inspection times, and inclusion or exclusion of subspecies or binational forms. Several lists (Contreras Balderas 1975, 1978a, b, 1987, in press) indicate ever-increasing numbers of imperiled species in Mexico, reflecting an increasing volume of available in-formation as well as changes in ecological conditions in the country. This paper considers two positive aspects of this problem: current protection of some habitats and fishes, and new legislation that authorizes and enhances such protection.